When a section of the system has a leak or malfunction ____________ are used to shut it off.

A)
filters
B)
control valves
C)
auxiliary power unit
D)
isolation valves

Correct Answer :   isolation valves


Explanation : Isolation valves help in shutting off the system if a leak or malfunction occurs within the system. Control valve varies the size of the passage and controls the flow. Filters does its job by retaining the contaminants from passing to the next level of the system.